1. Field of the Invention
This invention relates in general to certain new and useful improvements in gate-opening and closing apparatus and more particularly, to gate-opening and closing apparatus and methods therefore which shift a gate between an open and closed position and which also permits overriding by operatively disconnecting a drive member from a motive means as well as substantially simultaneously opening an automatic locking mechanism.
2. Brief Description of the Prior Art
In recent years, there have been a number of gate opening and closing assemblies and particularly, automatic type opening and closing assemblies. These gate assemblies have received increasing prominence in many commercial applications. There are several types of gates which are moved from a closed position to an open position in order to provide access and back to a closed position in order to provide a type of security. One type of gate is a gate which is slidable on a trackway, or other mechanism, for movement in a linear direction. This type of gate shifts from an open position in a linear path to a closed position in order to block the access opening. Other types of gates have one vertical side portion thereof hingedly mounted so that the other vertical side portion is swingable away from a stationary structure to an open position and back toward the stationary structure to a closed position.
As indicated previously, the automatic gate openers, in particular, have received increased prominence in recent years. These automatic gate openers may operate on the basis of a remote control mechanism such that a party desiring to open or close the gate does not have to physically engage the gate. For example, the gate opening and closing apparatus may use a radio transmitter and receiver system, such that a radio transmitter, when actuated, will generate a particular frequency signal which is sensed by the receiver to automatically operate the gate or door in order to open the same or close the same. In addition, and in many cases, the gates are controlled through key operated switch mechanisms, such that the user merely inserts a key into a key type switch and turns same to cause the completion of a circuit, thereby energizing or de-energizing a motor to permit movement of the gate.
With respect to the so-called "slider gates" that is gates which move in a generally linear path across the access opening, there have been significant problems in coupling these gate opening and closing apparatus to the sliding gate. One of the principal problems has been that the apparatus itself must be constructed so that it occupies only a small space and further, it must be capable of being located in a generally unobtrusive location.
Another one of the problems encountered with gates and the associated opening and closing apparatus is that of security. Typically, after the gate has been shifted to a closed position, there must be some type of positive locking action in order to prevent unauthorized opening of the gate. Finally, in the event of an emergency condition, such as a power failure, there must be some provision for overriding the entire apparatus so as to permit manual opening and closing of the gate.
In U.S. Pat. No. 4,159,599 dated July 3, 1979, by the same Applicant herein, there is provided a gate opening and closing assembly which is designed to shift a gate in a linear path between closed and open positions. This gate opening and closing assembly also used a drive motor along with a gear operable drive mechanism for rotating a pair of lever arms in order to shift a gate between the closed and open positions. A manually operable override mechanism was provided in this apparatus, although the override mechanism deals with the disengagement of a clutch.
The present invention obviates these and other problems in the provision of a gate opening and closing apparatus and method which automatically provides a positive locking action for a gate after the same has been shifted to a closed position and which is provided with an override means such that a drive member can be automatically disconnected from a motor and substantially simultaneously therewith the locking mechanism can be opened in order to permit emergency manual opening and closing of the gate.